Posted by If you have clicked on this link you already have a, probably, strong opinion on the topic. So I want to be clear from the first (second) line exactly what this article is NOT about. It is not about the spectacle of volleyball. It is not about teaching volleyball. It is not about educating spectators and fans about the game. For the record, I have an opinion on all those things, but they are different articles.
This article has one single goal, to answer the question ‘Do serve errors impact the outcome of a match negatively?’.
The best place to start is with actual matches that have been played, preferably a lot of matches.
I took the entire data set of the 2025 Volleyball Nations League, 117 matches in all. 18 of the top teams in the world participated, and each played at least 12 matches. We can reasonably assume that the matches were representative of men’s volleyball at the highest level. I then uploaded the matches into Science Untangled so we can do some analysis. The Volleyball Reporting app, includes the possibility to determine Win Indicators, i.e. how different statistical standards impact winning and losing.
The following chart represents the number of sets played and the number of serve errors per set. Green and red show whether a set is won or lost.
The eyeball test reveals that it looks remarkably even all the way through the range. The app also provides the option to set a particular level and the win probability is calculated. In the chart above the level is set at eight (8) serve errors per set. Eight serve errors occurs infrequently (only 5.6% of the time) but the team making 8 or more errors still wins over a third of the time.1
What happens if I check the difference in serve errors? Surely that would show something. The chart below shows the difference in serve errors.
If I set the standard at four (4), i.e. four more serve errors than the opponent, that the team still wins 40% of the time.
‘How can this be? You can’t just give away points’.
Firstly, this is what actually happens. It is not a trick of data. If what happens doesn’t fit an expectation, then it is necessary to review and revise the expectation.
The explanation, in many / most cases is maths. In a volleyball set, the number of sideouts won (i.e. points after the opponent’s serve), is equal for both teams, plus or minus one. It is inherent in the structure of the game. The difference in any set is the number of break points, i.e. points won on serve. We know that after every break point, the same team serves again. More break points equals more serves. Do you see where I’m going here? The team that wins the set has more serves and therefore has more opportunities for serve errors. For example, Team A wins 25-20 and has 25 serves while Team B has 20 serves. Both teams have 20% serve errors. Team A has 5 serve errors, Team B has 4 serve errors. Maths.
Maths dictates that serving more errors in a given set is not just possible, but indeed likely. The more one serves the more total errors.
After that we can talk about volleyball being an extremely complex interaction of multiple skills and situations performed under pressure with massive time constraints by humans with all their foibles. We can talk about the difficulty of scoring break points and the necessity (or not) of serving with high. But first we have to acknowledge maths.
- If you are wondering why the numbers don’t add up to 100, I was too. Here is an explanation:
Set 1: Team A (won) 8 errors, team B (lost) 4 errors
Set 2: Team A (won) 8 errors, team B (lost) 8 errors
>=8 errors = 3/4 (75%) of sets, 2/3 wins (67%)
<8 errors = 1/4 (25%) of sets, no wins (0%) ↩︎
At Home On The Court 
Hi Mark, thanks for these thought-provoking posts, especially this week “are serve errors important?” and next “threading the impossible needle”
I’ve been thinking about these posts in the weeks since, and I’m wondering if there is a hidden underlying assumption that may be masking something important, namely that service errors don’t matter because (or as long as) teams think they don’t matter. Both teams “go for it”, serve as strongly as possible and accept the errors as they come. Result: errors don’t matter, as shown.
But what happens if one team serves tactically while the other keeps the same strong-serve mentality? I’m not sure how one could parse the data to analyse that question, but I’m hoping that I am at least explaining my question clearly. Does (can) the data actually show that deliberately pursuing a strategy to minimize service errors is futile? (ie: What happens when a team that doesn’t care about service errors meets a team that deliberately tries to minimize them?)
In your post, even if the team makes 4+ more errors than the opponent, they still win 40% of the time. But isn’t that down from 50% when the errors are 3-?
In your ‘threading the needle’ post, Italy won points with or without the Belgian error. On that day, serving strategy may be irrelevant because Italy was just too good that day. But using a tactical serve, at least Italy still has to play. For a service error, they don’t even need to be on the court.
(For context, I coach girls secondary school / 17u club. There are lots of examples where “go for it” is absolutely the right mentality. I’m not advocating a “play safe” strategy, just wondering how to maximize effectiveness.)
Thanks again for your time and insights.
Cheers,
Dave
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Hay Dave. Thanks for the message.
The point of the first article, is that counting errors is misleading. It is misleading because the winning team serves more. Therefore, all things being equal, the winning team will always have more TOTAL errors.
‘Threading the needle’ is about the difficulty of finding the balance when the goal is to win the game. The game is structured in a way that you only have a limited number of opportunities to score points on serve. If you goal is to win, there is point when you have to score RIGHT NOW.
In general, everything depends on the relative strength of the teams. Against a weaker team, allowing them the chance to lose could be a valid strategy. Against a stronger team, it doesn’t work.
Personally, I have a nagging feeling that ‘at least they have to play it’ is less a strategy than the absence of strategy.
Keep smiling
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